User Manual

18
cellnetmiu Rev. 0
12/3/98 4:32 PM
SECTION 3
OPERATING INSTRUCTIONS
At the time of installation, the installer uses the CellNet installation tool to verify that the
Wall MIU1 is operating properly. Following the installation, the Wall
MIU1 operates
automatically and continuously without any type of human intervention.
SECTION 4
THEORY OF OPERATION
SURF ¨ MIU Programming
The MIU is not field programmable. At the factory, each of the following items are
programmed into the MIU:
Serial number - Each MIU is given a unique LAN address and a serial number/identification
number. Custom serial numbers are not programmed. The default value is the last
programmed value plus one.
Time between encoder register reads -The time between encoder register reads is set for
one hour.
Time between MIU transmissions - The time between MIU transmissions is set for
approximately 15 minutes
RF Protocol Error Detection
The RF protocol is comprised of a header, data packet, and an error detection mechanism
that reduces the erroneous data.
RF Transmission Period and Randomness
The random period generation uses the same CellNet ALOHA model to generate the transmit
randomness. The randomness algorithm is defined so that no two consecutive transmissions
from two MIUs will interfere with one another.
Low Battery RF Emissions
The MIU stops RF transmissions when the battery discharges below the normal operating
voltage.
TROUBLESHOOTING
Six-Wheel Encoder Normal Operation
If the odometer reads 123456, the display should be 1 2 3 4 5 5.
Note that the last digit displayed is a five if the last digit on the odometer is five through
nine. The last digit displayed is a zero if the last digit on the odometer is zero through four.
Four-Wheel Encoder Normal Operation
If the odometer reads 123456, the display should be 1 2 3 4 0 0.